Since its discovery nearly 10 years ago, hepatitis C has emerged as a major pathogen leading to development of cirrhosis, liver failure and hepatocellular carcinoma in a significant percentage of infected patients. Current treatment regimens lead to sustained viral clearance in less than 50 percent of treated patients and are associated with significant morbidity and cost. For these reasons, health-related quality of life issues have become an important part of the assessment of interventions. There are two primary methods to assess health-related quality of life. Most studies have focused on health status assessment, which describes functionality in one or more domains. There has been little research in health utility assessment which measures health values and ascertains the desirability of health states. Research in other chronic disease states demonstrates that there is poor correlation between health assessment and health utility. The determinants of health value are poorly understood. This one-year study has two primary aims: 1. Using specific health value and health status instruments, we will try to gain an understanding of health value (utilities) in patients with chronic hepatitis C infection and develop a predictive model of these values. 2. We will then try to gain a conceptual understanding of these health values. The study will be carried out in two parts. Part I will utilize the standard gamble, time-tradeoff and rating scale methodologies to generate utilities. These will be correlated to responses of a disease specific health status instrument which is a validated modification of the SF-36. Finally, the role of depression on value responses will be assessed with the aid of the Beck Depression Inventory. From these data, regression techniques will be used to develop a predictive model of health values in HCV infected patients. We will study 200 patients with HCV infection who have been stratified by specific stage/treatment specific categories. Part II will be the validation phase. We will attempt to develop a conceptual model of HCV-related health values by assessment of our predictive model and determination of the source of variability. Intensive individual interviews will be performed in 100 patients with HCV, stratified by liver disease stage, to determine how respondents understand health value questions and arrive at their responses.